Method of making glazed kid-leather



' hidesare also placed in the paddle wheel and No Drawing.

1 UNITED? STA E-S PATENT Q F'ICE- 'MIcHAEL A. znAnowsKI,0F.PHILADEL15HIA,PENNSYLVANIA.

ivmrnon OF MAKING GLAZED KID-"LEAT ER."

T0 aZZwho m it may concern} Be it known that I,- MICHAEL in-the city andcounty" of Philadelphia, State ofPennsylva'nia, have invented anew anduseful Method of Making Glazed Kid- 'Leather, of which the following isa speci- 'fication. f I e My present invention consists of a novelmethod of making glazed kid leather, and as a result of my novel method,the leather is waterproof, soft, elastic: and

plump, and has a smooth silky grain;

In carrying out my invention .in practice,

I take the skins 'or hides and firstsoak them in water to which salt hasbeen added in the proportion of one-half toone ounce-of common salt toone gallonof water.

The skins are then dehaired, forrexample by soaking in a solutionformedby boiling lime and red arsenic sulfid in water. The

skins arethen washed in water and bated in any desired manner, such asfor example, with dog manure;

' The skins are then subjected to threesuccessive tanning baths. Thefirst bath is formed by adding to one hundred gallons of water at atemperature ofabout 80 six to ten'pounds of salt, and from'oneto four 7pounds of sulfate of aluminum. Both the salt andthe sulfate of aluminumare separately' heated in closed pots before using,

in order to drive off any impurities.

The above solution'is usedto every hundred pounds of skins" This firstbath is placed in the paddle wheel and the skins or the latter is turnedfor about half an hour,

after which the skins are removed and drained. Thesulfateofaluminum isheated until it partially decomposes.

of .skins, one hundred gallons of water'at about 85 F. to whichis addedabout six pounds of dissolved potassium bichromate and about threepounds of muriatic acid at 21 B. For medium skins, I use for the useabout four pounds of potassiumbichromate and two and one-quarter poundsof muriatic acid; This second bath is placed in the paddle Wheel and theskins S peeificationof Letters Batent. I Application fi1ed'*A pri1:21,1917. Serial No. 133,582. a i V A. ZDANoW j SKI, a citizen of the UnitedStates,11es1d1ng one-degrees-Be. strength;

7 If the skins or hides are heavy, the second bath. is formed by takingfor-one hundred pounds I placed in the paddle wheel and the latterPatented my 1920. I f

turned until the solution" has thoroughly penetrated and treated i all,parts :of the skins.

1 The skins are thentaken out of: the solution and struckout and dippedsingly in a 3 five pounds of muriatic acid have been placed, and areplaced on wooden horses for about twelve hours. H l V V The skinsarethen treated in a third bath which for every hundred pounds of skinsor hides which are heavy 'is formed'by jtaking one hundred gallons ofwater, seventeen pounds of sodium thiosulfate and five pounds and teniouncesof ,muriatic acid, twenty-one degrees Baum. For one-hunpounds ofsodiunr 'thiosulfate and 'five ounds and five ounces of muriatic acid..or one hundred pounds of thin skins or hides, I use fifteen poundsofsodium thiosulfate and five pounds ofmuriatic acid. The muriatic acidin each case is "The skins or hides in the solution are placed in thepaddle Wheel which is turned until the skins assume a light blue color.The skins are then washed and struck out and shaved, after which I asusual.

By this process of tanning, the skins or hides can be tanned I by theuse of one-half to one percent. less of potassium bichromate than hasheretofore"been employed, with consequent reduction in the cost of pro-1ducing the leather. V c g Itwill be understood that instead I of paddlewheels, 'theskins can be tanned, in

they are coloreddred pounds of medium skins, I usesixteen ,twenty drums.After the tanning is completed, the] skins-v are again washed, struck"out, dyed as usual, o1led,d r1ed, and staked asv usual,-

and they are now ready for the seasoning.-

This seasoningis madeby taking five ounces of water, one dram ofnigrosine, two grains of carbohc acid #5, two "dramsof blood albumin orox blood, one dram of wood alcohol or ammonia, ten grains of gelatinorglue, and fifteen grains of formaldehyde. The skins are seasoned thenglazed, seasoned,

and glazed again and the resultant leather is waterproof,soft, elasticand plump, with a smooth silky grain.

I have found that by melting the salt J and; muriatic acid. i

In the seasoning operation, tl18S6LSOIl1Ilg,

used in the first tanning bath, I canemploy a cheap grade of salt. Itake the sulfate of aluminum in crystallized form and melt it in closedpots until it has the consistency of glue and then pour it out and allowit to cool. This purifies the sulfate of alumi- -num and renders'thefinished leather also more dampproof. By using a first bath of thischaracter, the skins become plump and smooth gbefore they are subjectedto the chrome process.

required; as the skinsare already.- partially tannedby the action of thesaltand the sulfate of, aluminum, v 2 4 f I also find hat vwhen theskins are placed in the thirdbatln-the actionof the sodiumhyposulfitefis-better, and a better tanning action is obtained By mymethod, I am enabled to employ 'asmaller amount of potassiumbichromate,- hypo-sulfite of soda material is rubbed; into the grainside of the skin inv the usual manner and the skins are then glazed by aglazing machine, using a glass agate,.such as is commonly used in themanufacture of leather.

Having thus described my invention, WllltI'ClELlID as newand desire tosecure by Letters Patent, is 1 1 l V I. The method of tanning whichcomprises soaking the skins in salt Water, de-

hairing, bating and then subjecting to three successive tanning baths,the first of said baths being formed by 'miXing together Water, salt andaluminum sulfate, the salt andaluminumsLu'lfate being melted in a closedreceptacle before using, the second bath being formed by mixing togetherwater, a bichromate and muriatic acid, and the third bath being formedbymixingtogether Water, sodium thiosulfate' and muriatic acid;

1 orthe hide. to three successive tanning baths, the first of said bathsbeing formed by mixing 800 parts of Water at a tempera ture of about80,-6 to 10 parts of salt and The salt in the skin con trols the actionof themuriatic acid and a 1 smaller amount of potassium bichromate isabout 4 parts of aluminum sulfate', the

second bath consisting of amixture of'800 parts of Water at 85 and asoluble 'bichro-' ornate and muriatic acid, the two latter being in theratio of about 2 :1, the third bath 7 consisting of about 800 parts ofWater con taining sodium' thiosulfate and muriatic acid, the two latterbeing in about the; a

ratio of 3 :1. a

4. The method of tanninghide which consists in subjecting hide to theaction of three successive baths, the first. of which is V formedbydissolving saltand sulfate of aluminum, areviously fused, in WarmWater,- the second bath consist ng of a warm acidified solution of asoluble bichromate and,

the third bath consisting of an acidified solution of a thiosulfate, V,

5. The improvement in the art of tanning which consists in; subjectingthe skins .to' the action of a tanning'bath 'containing salt andaluminum sulfate, the said salt andaluminum sulfate being each meltedbefore dissolving the same in Water. a

i 6. The improvement inthe art of tanning which consists in subjectingthe skins to the action of a tanning bathcontaining about 6'to 10 poundsof salt and about 1 to 4i pounds of aluminum sulfate to each 100 gallonsof Water, the salt and aluminum sulfate being melted before-dissolvingthem I invvater. i r

7. The method of tanning hide, which it consists in subjecting each 100pounds of the hide to three successive baths,the first of which contains6 to 10 pounds of common salt, 1 to 4 pounds of aluminum sulfate, thesecond of Whichcontainsto gallons of Warm Water about four one-f halfpounds of an alkali metal bichromate and abouttwo and one-quarterpoundsof muriatic acid, the third bath, containing about 15 pounds ofsodiumthiosulfate. and 7 about pounds of muriatic acid.

8. The process of tanning, which comprises the succession of steps of(a) subjectingtlie depilatedand bated hides'to a solution containingpreviously melted salt and aluminum sulfate, thereaftersubjecting thesame totreatment with an acidi fiedi chromatev solution, and thereaftersubjecting the same to a solution of ,hypo- 9. In the preparation of atanning solution, containing salt and aluminum sulfate,

the step of melting the salt and aluminum sulfate before dissolving thesame in Water.

MICHAEL A. ZDANo sKL rlvitnessesz V V I r H, S. FAIRBANKS,

(L D. MOVAY.

